Process for dyeing viscose rayon and nylon with subsequent fixation in a halogenated hydrocarbon bath



United States Patent US. Cl. 854.2 Claims ABSTRACT OF THE DISCLOSURE Textile materials are dyed by treating the textile material with a dyestutf composition and fixing the dye thereof by passing the textile material through liquid halogenated hydrocarbons at 70 C. up to the boiling point thereof.

This invention relates to a dyeing process, and more particularly to a process for dyeing textile materials continuously in long lengths.

In conventional continuous dyeing practice, textile materials are commonly impregnated with an aqueous solution or suspension of the dyestuff and the impregnated textile material is then subjected to a heat treatment to fix the dyestufi. on the textile material. This heat treatment can be carried out in a variety of ways, depending upon the particular type of dyestuffs employed and machinery available.

We have now found that a very convenient way of carrying out the heating stage is by immersing the impregnated textile material in a bath of halogenated hydrocarbon solvent at the required temperature.

Thugjaccording to our invention we provide an improvgdfprocess for dyeing textile materials which compris'si'impregnating the textile material With a composition containing the dyestufi and then immersing the impregnated textile material in a bath of liquid halogenated hydrocarbon at a temperature conducive to fixation of the'dyestuif on the textile material. The composition containing the dyestuff is preferably an aqueous compositionfflf? The ibest results are usually obtained when using a textil inaterial which is hydrophilic in nature, particularly vi's 'e'fose rayon, though other textile materials which can bd'jdyed from aqueous baths or by aqueous compositions for example nylon) can also be treated by our process if so desired. The textile materials may be in any convenient form, whether woven, spun or otherwise, but it is found that the process is most advantageous when the textile material is in long lengths and is passed con tinuously through the bath of chlorinated hydrocarbon. It is especially suitable for dyeing viscose yarn for use in the manufacture of carpeting.

The impregnation of the textile material with the dyestutf may be carried out in conventional manner, for example by padding techniques and particularly by ran dom dyeing, that is to say, by the localised application of a dyestuff or a plurality of dyestuifs on a yarn web by passage of the web between rollers having an irregular surface, the lower roller serving as a pick-up roller. The aq "ejous medium containing the dyestuff may be an aqueousj fsolution or suspension of the dyestuff, and is essentially the same as that used for other methods of dyeing in which the dyestuif is fixed on the textile material by heat. The aqueous medium may contain any of 3,523,749 Patented Aug. 11, 1970 "ice the conventional or known additives or adjuvants (including wetting agents, thickening agents, migration inhibitors, solubilising agents, mild oxidising agents, acids or acidproducing agents, acid-binding agents, and mixtures thereof) as may be appropriate to the particular dyestutf and textile material concerned. The impregnation may be carried out in a single stage, or in multiple stages using the same or different aqueous media in succession, as desired. Also the proportions of impregnating medium to textile material may be essentially those already wellknown.

There are, however, the joint problems of getting sufficient dyestutf into the textile material at the impregnation stage and the subsequent removal of the water content of the dyestuff composition in the dye-fixing step, in which the impregnated textile material is immersed in the hot bath of a liquid chlorinated hydrocarbon.

To assist in solving both these problems the dyestuif composition may be applied to the textile material in the form of an emulsion-thickened composition.

Emulsion-thickened compositions are Well known in the art, and consist of oil-in-water or Water-in-oil emulsions in which the oil phase consists of a substantially water-immiscible organic liquid, which may be for example a hydrocarbon or a halogenated hydrocarbon or a mixture of these. Particular examples of liquids which may be used include petroleum fractions (especially kerosene) and halogenated hydrocarbons such as chlorinated methanes and chlorinated ethanes (especially methylchloroform, trichloroethylene, perchloroethylene, carbon tetrachloride and mixtures thereof). The emulsions may be made by established techniques, and may employ emulsifying agents and the like to assist formation and/ or stabilization of the emulsions.

The chlorinated hydrocarbons are to be preferred, because they are much less inflammable than the hydrocarbons, and may in many cases be completely non-inflammable. To secure satisfactory emulsions, however, mixtures may have to be used.

When the oil-phase of the emulsion is not the same as the chlorinated hydrocarbon used for the final dyefixing step, it must be remembered that the emulsionforming liquid will become dissolved in the heating bath and will tend to accumulate in it. Consequently, allowance for this will be required in any procedure, for example distillation, used to purify and recover the chlorinated solvent for re-use. It is most convenient to arrange that, if the emulsifying and heating liquids are not the same, the emulsifying liquid has a sufiiciently higher boiling point than the other to enable the purifying distillation step to yield the purified chlorinated solvent as distillate and to leave the emulsifying liquid in the boiler residue. Especial care needs to be taken when the emulsifying liquid contains a hydrocarbon since this can lead to a fire or explosion hazard, by accumulation either in the heating bath or in the distillate.

These emulsiorrthickened compositions have the wellknown advantage of requiring no Water-insoluble or involatile thickening agents, such as gums or dextrins, which may be difficult to remove from the textile material. In addition, we find that they enable the proportion of water in the dyestuff composition applied to the texile material (and which subsequently has to be removed) to be reduced considerably, they tend to improve the evenness of the dyeing, and they are completely dissolved in the chlorinated hydrocarbon solvent bath.

As a result of most of the techniques used for the application of the dye a lot of Water is introduced into the chlorinated hydrocarbon bath and must be removed from it, and in these circumstances there is sometimes a tendency for the water coming off the textile material to accumulate as globules in the chlorinated hydrocarbon.

3 When this occurs, these globules tend to be picked up again by the textile material and give rise to irregular dyeing.

This effect can be minimised by adding a dispersing agent to the chlorinated hydrocarbon bath, to assist dispersion of the water rapidly through the bath and to keep the water in a highly dispersed state without appreciable growth of globules. As the bath is hot, and usually at or near its boiling point, the dispersed water is rapidly removed, in the case of chlorinated hydrocarbons by azeotropic boiling, and the presence of the dispersing agent facilitates this by preventing local accumulations of water, for example as a layer on the surface of the bath.

The dispersing agent may be, in general, any agent which assists the dispersion of water in the chlorinated hydrocarbon. Suitable agents include non-ionic, anionic and cationic agents, and mixtures thereof. The choice of agent depends primarily upon the nature of the textile material 'and the dyestuff employed, and care may need to be exercised to avoid using an agent which could have an adverse effect on the dyeing process, for example by changing the shade of the dyestuff. A large variety of dispersing agents (alternatively termed surface-active agents or emulsifying agents) is well known in the art and their compatibility with particular dyestuffs is either well established or can be ascertained by simple trial; any dispersing agent satisfactory in this respect and also soluble in the chlorinated hydrocarbon can be used in our process.

Examples of suitable dispersing agents include longchain quaternary ammonium compounds, for example cetyl-pyridiniurn and cetyl trimethyl ammonium salts, dodecylbenzenesulphonate salts, and ethylene oxide condensates of fatty acids, long-chain aliphatic amines or amides, or fatty alcohols.

Suitable concentrations of the dispersing agent are usually in the range 1% to 5% by weight of the chlorinated hydrocarbon solvent, though larger or smaller proportions may sometimes be found to be suitable. The chlorinated solvent bath may be agitated mechanically to assist dispersion of the water, but if the bath is maintained at or near the boiling point thermal agitation is usually sufficiently effective.

The dyestuff is most suitably a reactive dyestuff (i.e. a dyestuff which can react chemically with the textile material) for example a dyestuff containing a chloro-striazine or dichloro-s-triazine radical. Other dyestuffs for example direct dyes may also be used if desired.

The halogenated hydrocarbon may be an individual compound or a mixture, and should be of any appropriate boiling point (preferably above about 70 C.) which allows the bath to be maintained at the temperature required for fixation of the dyestufi. We have found that it is desirable though not essential to maintain the temperature of the halogenated hydrocarbon bath above about 70 C. and preferably above about 100 C. Suitable halogenated hydrocarbons include trichloroethylene, 1,1,1- trichloroethane, perchloroethylene and mixtures thereof. Perchloroethylene is preferred because of its conveniently high boiling point.

The time required for the immersion in the liquid halogenated hydrocarbon depends to a considerable extent upon the nature of the particular textile material and dyestuff employed, but is preferably in the range 5-60 seconds.

The bath of halogenated hydrocarbon may be contained in any conventional apparatus designed or adapted for use in the solvent treatment of textiles, and may he provided with any of the known arrangements for carrying the textile material through the bath, for recovering or purifying the solvent during use, and the like.

After emerging from the bath, the textile material may be treated by any of the known or conventional techniques appropriate to the finishing of the dyed material,

4 for example by washing, drying and resin-finishing operations.

The invention is illustrated but not limited by the following examples in which the parts and percentages are by weight unless otherwise stated:

EXAMPLE 1 Staple viscose rayon carpet yarn was padded 'With an aqueous dye solution containing, per 1000 parts, 20 parts of the dye obtained by condensing cyanuric chloride (1 mole) with 1 mole of 1-( 4'-sulphophenyl)-3-carboxy-4- (2"-sulpho-5"-a-minophenylazo)-5-pyrazolone, 10 parts of sodium bicarbonate and 2 parts of sodium tri-iso-propylnaphthalene sulphonate. The yarn was squeezed between rollers set to allow retention by the yarn of its own weight of dye liquor, and was then immersed for 8 seconds in boiling perchloroethylene. The yarn was then dried, thoroughly rinsed in cold water, washed for 15 minutes in a boiling solution of 3 parts of a mixture of a nonionic and an anionic detergent in 1000 parts water and finally rinsed in water and dried. The yarn was dyed a deep bright greenish-yellow shade of a very high light fastness and washing fastness.

When the procedure of the above example was repeated except that in place of the above dyestuff there was used the dyestuff described in Example 1 of UK. patent specification No. 209,723, a bright bluish-red dyeing 'was obtained. I

EXAMPLE 2 Staple nylon 66 yarn was, in separate experiments, padded with an aqueous dye solution containing, per 1000 parts, 100 parts of urea, 10 parts of ammonium dihydrogen phosphate, 2 parts of a condensation product of nonyl phenol and ethylene oxide and 20 parts of the acid dyes (a) obtained by diazotisation of o-aminobenzene-N-ethyl anilide and coupling the resulting diazo compound with Z-amino-8-naphthol-6-sulphonic acid, (b) the dyestuff recorded in the Colour Index as Acid Blue 41 (CI 62130) and (c) the dyestuff recorded in the Colour Index as Acid Orange 3 (CI 10385). The yarn was squezeed through rollers to allow retention by the yarn of its own weight of dye liquor and was then immersed for 15 seconds in boiling perchloroethylene. The yarn was then dried, thoroughly rinsed in cold water and finally dried. The yarn was dyed a deep bright shade of respectively (a) red, (b) blue and (c) yellow.

Repetition of the process with each of the three dyes described above and using a bath of perchloroethylene at temperatures of 100 C., C. and 80 C. gave yarns of lighter, but acceptable shades. The difference in depth of shade between yarn treated in 'boiling perchloroethylene and that treated at C. is considerably greater than the difference in depth of shade between yarn treated at 100 C. and 80 C.

What we claim is:

1. Process for dyeing a textile material selected from the group consisting of viscose rayon and nylon which comprises impregnating the textile material with a dyestutf composition consisting essentially of a dyestuff selected from the group consisting of a reactive dyestuff and direct dyestuff and subsequently immersing the impregnated textile material in a bath of liquid halogenated aliphatic hydrocarbon at a temperature from 70 C. up to the boiling point, which temperature is conductive to fixation of the dyestufi on the textile material.

2. Process as claimed in claim 1 wherein the composition containing the dyestuff is an aqueous composition.

3. Process as claimed in claim 1 when applied to long lengths of textile material which are passed continuously through the bath of chlorinated hydrocarbon.

4. Process as claimed in claim 1 wherein the composition containing the dyestuff is applied to the textile material by padding.

5. Process as claimed in claim 1 wherein the composition containing the dyestutf is applied to the textile material by random dyeing.

6. Process as claimed in claim 1 wherein the dyestuff is a reactive dyestuff.

7. Process as claimed in claim 6 wherein the dyestuif contains a chloro-s-triazine radical.

8. Process as'clairned in claim 1 wherein the halogenated hydrocarbon comprises perchloroethylene.

9. Process as claimed in claim 1 wherein the halogenated hydrocarbon comprises trichloroethylene or 1,1,1- trichloroethane.

10. Process as claimed in claim 1 wherein the time of immersion in the halogenated hydrocarbon is in the range 5-60 seconds.

11. Process as claimed in claim 1 wherein the temperature of the halogenated hydrocarbon bath is above 100 C.

12. Process as claimed in claim 1 wherein the halogenated hydrocarbon bath is boiling.

13. Process of claim 8 wherein the said dyestulf is contained in an aqueous composition.

14. Textile material dyed by a process claimed in claim 1.

15. Process as claimed in claim 2 wherein the composition containing the dyestutf is an emulsion-thickened aqueous composition.

16. Process as claimed in claim wherein the emulsion-thickened composition contains a halogenated hydrocarbon.

17. Process as claimed in claim 16 wherein the emulsion-thickened composition contains the same halogenated hydrocarbon as the bath of liquid halogenated hydrocarbon.

18. A process for dyeing a textile material selected from the group consisting of viscose rayon or nylon which comprise impregnating the textile material with a dyestufl composition consisting essentially of chloro-striazine azo reactive dyes and direct dyes and immersing the impregnated textile material in a bath of liquid halogenated aliphatic hydrocarbon at a temperature from C. up to the boiling point thereof.

19. Process as claimed in claim 1 wherein a dispersing agent selected from the group consisting of a long-chain quaternary ammonium compound, a dodecylbenzenesulphonate salt, or a condensate of ethyene oxide with a fatty acid, or a long-chain aliphatic amine, amide or alcohol is present in the chlorinated hydrocarbon bath.

20. Process as claimed claim 19 wherein the concentration of dispersing agent is in the range 1%t0 5% by wieght of the chlorinated hydrocarbon solvent.

References Cited UNITED STATES PATENTS 2,274,751 3/ 1942 Sowter et al 8-59 2,828,180 3/1958 Sertorio 8-93 X 2,999,002 9/1961 Dayvault et al. 8-94 1,533,769 4/1925 Scholz 8--74 3,215,486 11/ 1965 Hada et a1. 8-74 FOREIGN PATENTS 768,745 2/ 1957 Great Britain.

GEORGE F. LEMMES, Primary Examiner T. J. HERBERT, JR., Assistant Examiner US. Cl. X.R. 8-163, 94, 166, 178 

